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Unformatted text preview: evated. Megaloblastic Anaemia
Megaloblastic Causes of vitamin B12 deficiency:
1. Inadequate intake.
2. Intrinsic factor deficiency Gastrectomy Gastric atrophy ( Pernicious anemia)
3. Diseases of terminal ileum
(site of B12 absorption).
4. Removal of vitamin B12 from intestine by (Fish tapeworm). parasites Causes of folic acid deficiency: 1. A decrease in folic acid intake.
(Folate is mainly absorbed in jejunum)
3. An increase demand for folic acid. ( ex. Pregnancy & Hemolysis) Megaloblastic Anaemia
Megaloblastic Why the size of RBCs is increased in megaloblastic anemia?
If vitamin B12 &/or folic acid supply is less, the ability of bone marrow cells to synthesize DNA is decreased. This leads to slow division & less reproduction of cells. The RNA synthesize in the cytoplasm of dividing cells is not affected, so the RNA amount is more than normal resulting in excess production of cytoplasmic Hb & other organelles inside developing RBC leading to large size RBC. Megalob...
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- Spring '14